Paste dispenser

Abstract

A paste dispenser includes a bottle, a piston, an elastic element, and a switch. The bottle includes a main body and a neck connected to the main body. The main body includes a bottom wall facing the neck. The piston is received in the main body, and hermetically divides the bottle into a first and a second receiving spaces. The first receiving space receives paste. The first elastic element is compressed between the bottom wall and the piston. An uncompressed length of the first elastic element is equal to or greater than a length of the main body. The switch is mounted on the neck and used for controlling the flow rate of the paste. When the switch is turned on, the first elastic element pushes the piston to squeeze the paste out of the neck. When the switch is turned off, the first receiving space is sealed up.

1 . A paste dispenser comprising:
 a hollow bottle which comprises a main body and a neck connected to the main body, the main body having a bottom wall facing the neck;   a piston received in the main body and providing a hermetic seal with a sidewall of the main body, and thus to divide the bottle into a first receiving space and a second receiving space, wherein the first receiving space is configured for receiving paste;   a first elastic element received in the second receiving space, the first elastic element being compressed between the bottom wall and the piston, and thus the first elastic element capable of pushing the piston towards the neck, wherein an uncompressed length of the first elastic element is equal to or greater than a length of the main body; and   a switch mounted on the neck, and configured for controlling the flow rate of the paste, wherein when the switch is turned on, the paste is pushed by the piston to flow outside from the neck, when the switch is turned off, the paste is sealed in the first receiving space.   
     
     
         2 . The paste dispenser of  claim 1 , wherein the bottom wall defines an air inlet, the second receiving space is communicating with the outside of the paste dispenser through the air inlet. 
     
     
         3 . The paste dispenser of  claim 1 , wherein the piston comprises a first surface, a second surface opposite to the first surface, and a sidewall connecting to the first surface and the second surface, the sidewall defines a continuous slot along the circumference thereof, the piston comprises a resilient plastic seal filling up the slot and contacting the sidewall of the main body, the first elastic element is compressed between the bottom wall and the second surface. 
     
     
         4 . The paste dispenser of  claim 3 , wherein the main body tapers from the neck towards the bottom wall, the resilient plastic seal is capable of expanding from the slot to contact the sidewall of the main body when the piston moves towards the neck, and thus the paste is hermetically sealed in the first receiving space. 
     
     
         5 . The paste dispenser of  claim 1 , wherein the switch is a valve, the valve comprises a stopper, the neck defines a first through hole for providing an outlet from the main body, a sidewall of the neck defines a second through hole communicating with the first through hole, the stopper movably extends through the second through hole, and is thus capable of opening or plugging the first through hole. 
     
     
         6 . The paste dispenser of  claim 5 , wherein an inner surface of the sidewall of the neck further defines a receiving groove aligned with the second through hole, when one end of the stopper is received in the receiving groove, the first through hole is sealed up. 
     
     
         7 . The paste dispenser of  claim 5 , wherein the switch further comprises a handle extending from the stopper and positioned outside the bottle. 
     
     
         8 . The paste dispenser of  claim 7 , wherein the switch further comprises a second elastic element, the second elastic element is positioned between the neck and the handle and configured for providing an elastic force to push the handle and stopper away from the neck. 
     
     
         9 . The paste dispenser of  claim 8 , wherein an outer surface of the neck defines a first fixing groove coaxial with the second through hole, a surface of the handle facing the neck defines a second fixing groove spatially corresponding to the first fixing groove, two opposite ends of the second elastic element are respectively received and positioned in the first fixing groove and the second fixing groove. 
     
     
         10 . The paste dispenser of  claim 1 , wherein the main body comprises a first portion and a second portion coaxial with the first portion and connected to the first portion, the first portion is connected to the neck, the second portion comprises the bottom wall.